2008-10-30 00:59:21

by Mingming Cao

[permalink] [raw]
Subject: [RFC PATCH 2/3] quota: Add quota claim and release reserved quota blocks operations

quota: Add quota claim and release reserved quota blocks operations

Reserved quota will be claimed at the block allocation time. Over-booked
quota could be returned back with the release callback function.

Signed-off-by: Mingming Cao <[email protected]>
---
fs/dquot.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++
include/linux/quota.h | 2 +
include/linux/quotaops.h | 47 +++++++++++++++++++++++++++++++++++++++
3 files changed, 105 insertions(+)

Index: linux-2.6.28-rc2/include/linux/quota.h
===================================================================
--- linux-2.6.28-rc2.orig/include/linux/quota.h 2008-10-28 17:35:08.000000000 -0700
+++ linux-2.6.28-rc2/include/linux/quota.h 2008-10-28 17:35:17.000000000 -0700
@@ -293,6 +293,8 @@ struct dquot_operations {
int (*mark_dirty) (struct dquot *); /* Dquot is marked dirty */
int (*write_info) (struct super_block *, int); /* Write of quota "superblock" */
int (*reserve_space) (struct inode *, qsize_t, int); /* reserve quota for delayed block allocation */
+ int (*claim_space) (struct inode *, qsize_t); /* claim reserved quota for delayed block allocation */
+ void (*release_rsv) (struct inode *, qsize_t); /* release reserved quota for delayed block allocation */
};

/* Operations handling requests from userspace */
Index: linux-2.6.28-rc2/include/linux/quotaops.h
===================================================================
--- linux-2.6.28-rc2.orig/include/linux/quotaops.h 2008-10-28 17:35:08.000000000 -0700
+++ linux-2.6.28-rc2/include/linux/quotaops.h 2008-10-28 17:35:17.000000000 -0700
@@ -28,6 +28,11 @@ int dquot_drop(struct inode *inode);
int dquot_alloc_space(struct inode *inode, qsize_t number, int prealloc);
int dquot_alloc_inode(const struct inode *inode, qsize_t number);

+int dquot_reserve_space(struct inode *inode, qsize_t number, int prealloc);
+int dquot_claim_space(struct inode *inode, qsize_t number);
+void dquot_release_reserved_space(struct inode *inode, qsize_t number);
+
+
int dquot_free_space(struct inode *inode, qsize_t number);
int dquot_free_inode(const struct inode *inode, qsize_t number);

@@ -196,6 +201,31 @@ static inline int vfs_dq_alloc_inode(str
return 0;
}

+/*
+ * Convert in-memory reserved quotas to real consumed quotas
+ */
+static inline int vfs_dq_claim_space(struct inode *inode, qsize_t nr)
+{
+ if (sb_any_quota_active(inode->i_sb)){
+ if (inode->i_sb->dq_op->claim_space(inode, nr) == NO_QUOTA)
+ return 1;
+ }
+ else
+ inode_add_bytes(inode, nr);
+
+ mark_inode_dirty(inode);
+ return 0;
+}
+
+/*
+ * Release reserved (in-memory) quotas
+ */
+static inline void vfs_dq_release_reservation_space(struct inode *inode, qsize_t nr)
+{
+ if (sb_any_quota_active(inode->i_sb))
+ inode->i_sb->dq_op->release_rsv(inode, nr);
+}
+
static inline void vfs_dq_free_space_nodirty(struct inode *inode, qsize_t nr)
{
if (sb_any_quota_active(inode->i_sb))
@@ -342,6 +372,16 @@ static inline int vfs_dq_reserve_space(s
return 0;
}

+static inline int vfs_dq_claim_space(struct inode *inode, qsize_t nr)
+{
+ return vfs_dq_alloc_space(inode, nr);
+}
+
+static inline int vfs_dq_release_reservation_space(struct inode *inode, qsize_t nr)
+{
+ return 0;
+}
+
static inline void vfs_dq_free_space_nodirty(struct inode *inode, qsize_t nr)
{
inode_sub_bytes(inode, nr);
@@ -386,6 +426,17 @@ static inline int vfs_dq_reserve_block(s
nr << inode->i_sb->s_blocksize_bits);
}

+static inline int vfs_dq_claim_block(struct inode *inode, qsize_t nr)
+{
+ return vfs_dq_claim_space(inode,
+ nr << inode->i_sb->s_blocksize_bits);
+}
+
+static inline void vfs_dq_release_reservation(struct inode *inode, qsize_t nr)
+{
+ vfs_dq_release_reservation_space(inode, nr << inode->i_sb->s_blocksize_bits);
+}
+
static inline void vfs_dq_free_block_nodirty(struct inode *inode, qsize_t nr)
{
vfs_dq_free_space_nodirty(inode, nr << inode->i_sb->s_blocksize_bits);
@@ -415,6 +466,8 @@ static inline void vfs_dq_free_block(str
vfs_dq_alloc_block_nodirty(inode, nr)
#define DQUOT_ALLOC_BLOCK(inode, nr) vfs_dq_alloc_block(inode, nr)
#define DQUOT_RESERVE_BLOCK(inode, nr) vfs_dq_reserve_block(inode, nr)
+#define DQUOT_CLAIM_BLOCK(inode, nr) vfs_dq_claim_block(inode, nr)
+#define DQUOT_RELEASE_RSV_BLOCK(inode, nr) vfs_dq_release_reservation(inode, nr)
#define DQUOT_ALLOC_INODE(inode) vfs_dq_alloc_inode(inode)
#define DQUOT_FREE_SPACE_NODIRTY(inode, nr) \
vfs_dq_free_space_nodirty(inode, nr)
Index: linux-2.6.28-rc2/fs/dquot.c
===================================================================
--- linux-2.6.28-rc2.orig/fs/dquot.c 2008-10-28 17:35:08.000000000 -0700
+++ linux-2.6.28-rc2/fs/dquot.c 2008-10-28 17:37:56.000000000 -0700
@@ -846,6 +846,24 @@ static inline void dquot_resv_space(stru
dquot->dq_dqb.dqb_rsvspace += number;
}

+/*
+ * Claim reserved quota space
+ */
+static int dquot_claim_reserved_space(struct dquot *dquot,
+ qsize_t number)
+{
+ if (dquot->dq_dqb.dqb_rsvspace < number) {
+ printk("WARNING: reserved quota %llu is not enough for"
+ "request %llu bytes\n",
+ dquot->dq_dqb.dqb_rsvspace, number);
+ return 1;
+ }
+
+ dquot->dq_dqb.dqb_curspace += number;
+ dquot->dq_dqb.dqb_rsvspace -= number;
+ return 0;
+}
+
static inline void dquot_decr_inodes(struct dquot *dquot, qsize_t number)
{
if (dquot->dq_dqb.dqb_curinodes > number)
@@ -1325,6 +1343,69 @@ int dquot_reserve_space(struct inode *in
return ret;
}

+int dquot_claim_space(struct inode *inode, qsize_t number)
+{
+ int cnt;
+ int ret = QUOTA_OK;
+
+ if (IS_NOQUOTA(inode)) {
+ inode_add_bytes(inode, number);
+ return ret;
+ }
+
+ down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ if (IS_NOQUOTA(inode)) {
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ inode_add_bytes(inode, number);
+ return ret;
+ }
+
+ /* Dirtify all the dquots - this can block when journalling */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (inode->i_dquot[cnt] != NODQUOT)
+ ret = dquot_claim_reserved_space(inode->i_dquot[cnt],
+ number);
+ }
+ if (ret == NO_QUOTA) {
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ return ret;
+ }
+ /* Dirtify all the dquots - this can block when journalling */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+ if (inode->i_dquot[cnt])
+ mark_dquot_dirty(inode->i_dquot[cnt]);
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ inode_add_bytes(inode, number);
+ return ret;
+}
+
+/*
+ * Release reserved quota space
+ */
+void dquot_release_reserved_space(struct inode *inode, qsize_t number)
+{
+ int cnt;
+ struct dquot *dquot;
+
+ if (IS_NOQUOTA(inode))
+ return;
+
+ down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ if (IS_NOQUOTA(inode)) {
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+ return;
+ }
+
+ /* Dirtify all the dquots - this can block when journalling */
+ for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+ if (inode->i_dquot[cnt] != NODQUOT) {
+ dquot = inode->i_dquot[cnt];
+ dquot->dq_dqb.dqb_rsvspace -= number;
+ }
+ }
+ up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+}
+
/*
* This operation can block, but only after everything is updated
*/
@@ -2349,7 +2430,9 @@ EXPORT_SYMBOL(dquot_alloc_space);
EXPORT_SYMBOL(dquot_alloc_inode);
EXPORT_SYMBOL(dquot_free_space);
EXPORT_SYMBOL(dquot_free_inode);
-EXPORT_SYMBOL (dquot_reserve_space);
+EXPORT_SYMBOL(dquot_reserve_space);
+EXPORT_SYMBOL(dquot_claim_space);
+EXPORT_SYMBOL(dquot_release_reserved_space);
EXPORT_SYMBOL(dquot_transfer);
EXPORT_SYMBOL(vfs_dq_transfer);
EXPORT_SYMBOL(vfs_dq_quota_on_remount);